Effect of Dexamethasone on proliferation and expression of fibroblast growth factor mRNA in human embryo lung fibroblasts exposed to hyperoxia / 中华实用儿科临床杂志

ABSTRACT

Objective To explore the effect of Dexamethasone(DEX)on the proliferation and the expression of fibroblast growth factor(FGF)- 1,FGF - 2 and interleukin - 6(IL - 6)mRNA in hyperoxia - exposed human em-bryo lung fibroblasts(MRC - 5). Methods High oxygen volume fraction of 950 mL/ L was used to establish hyperoxia -damaged cell models,then treated with different concentrations of DEX(10 - 4 ,10 - 6 ,10 - 8 ,10 - 9 ,10 - 10 ,10 - 11 ,10 - 12 mol/ L),respectively. The proliferation activity of the cells was evaluated by methyl thiazolyl tetrazolium(MTT)at 24 h,48 h,72 h,and the optimal hyperoxia - exposed time and concentration of DEX were chosen;then they were divided into air group,hyperoxia group and hyperoxia + DEX group. The mRNA expressions of FGF - 1,FGF - 2 and IL - 6 were detected by quantitative real - time PCR at 48 h. Results Cell proliferation activity of the hyperoxia group was lower than that of the air group and there were significant differences at 48 h and 72 h(all P ﹤ 0. 05). Compared with the hyperoxia group,cell proliferation activity of the hyperoxia + DEX group increased with the concentration of DEX decreasing,reaching the peak at 10 - 9 mol/ L,and then gradually decreased with the concentration of DEX decreasing. Cells were cultured for 48 h,compared with the air group,the level of FGF - 1 mRNA was lower,FGF - 2 and IL - 6 mRNA were higher in the hyperoxia group(P ﹤ 0. 05). Compared with hyperoxia group,the level of FGF - 1 mRNA was higher,FGF - 2 and IL - 6 mRNA were lower in hyperoxia + DEX group(P ﹤ 0. 05). Conclusions Exposure to high oxygen volume fraction of 950 mL/ L for 48 h can cultivate optimal hyperoxia - damaged cell models,and DEX can protect the cell from hyperoxia injury and 10 - 9 mol/ L was the optimal concentration. Enhanced the expression of FGF - 1 mRNA and inhibited expression of FGF - 2 mRNA may be one of the mechanism that DEX protects the cells from hyperoxia injury.